Is CO2 from Cars Not as Bad as Methane from Landfills?

• New study from the United Nations spotlights global methane pollution.
• Methane increases global warming far quicker than CO2.
• Cars produce 10 percent (or more) of pollutants that cause global warming.

I like cars, you like cars, that’s why we’re here, talking about cars. But do cars get a disproportionate amount of blame for pollution?

While government regulations target our beloved automobiles and other sources of harmful emissions to try to limit greenhouse gases, you could argue that targeting methane released into the atmosphere is more important.

You already know that our own US Environmental Protection Agency seeks to control gaseous or particulate pollutants released into the air from industrial, mobile, and area sources to ensure compliance with air quality standards. They focus on six criteria pollutants, including nitrogen dioxide (NO2), sulfur dioxide (SO2), particulate matter (PM-10, PM-2.5), and greenhouse gases.

But a recent study by the United Nations Environment Program (UNEP), the self-proclaimed leading global authority on the environment, shows how bad methane is compared to emissions from cars and other sources. UNEP has 30 satellites circling the globe looking for methane leaks.

Cars produce 10 percent of GHGs worldwide.

Why?

Methane (CH4) is far more potent than carbon dioxide (CO2) at trapping heat over the short term (80+ times more potent over a 20-years period UNEP says), while CO2 is worse over the long term because it persists for centuries, according to the Environmental Defense Fund and numerous other sources. Methane drives immediate, intense warming, whereas CO2 acts as the primary driver of long-term climate change. Methane is responsible for about 30% of global warming since pre-industrial time, the EDF says. Human activity is responsible for 60 percent of the methane in the atmosphere, according to NASA, which also monitors the gas.

What UNEP’s satellites found was that methane from landfills, oil and gas fields, and coal mines were the biggest offenders. Kazakhstan and Turkmenistan are the two biggest-offending countries, but we, the US of A, are also on the list.

The single largest source of methane in the world was a landfill outside of Santiago, Chile, that releases over 100,000 metric tons of methane a year, though that number has been mitigated by methane capture that fuels a nearby power station.

After Chile’s landfill, the top methane-releasing spots in the world are found in Turkmenistan, India, Thailand and China, but the list covers the globe. We in the United States have a venting shaft from a metallurgical coal mine in West Virginia that sits at number 46 on the world’s Top 50 list.

The Los Colorados landfill outside Santiago, Chile emits more methane than anywhere else in the world.

UNEP identified over 350 “Notified Sources” of methane in the US, two percent of which are being mitigated. We’re not alone, of course, there are sources of methane all over the globe.

You can see the UNEP paper here, and more info on methane pollution from NASA here. But if you’re going to write your congressional representative about pollution, be sure to include methane in the list of pollutants that should be addressed.

“While methane causes more immediate damage, CO2 is the dominant, persistent cause of long-term warming,” UNEP says. “Therefore, reducing methane offers a rapid way to reduce near-term warming, but long-term climate stability requires reducing CO2.”

Mark Vaughn grew up in a Ford family and spent many hours holding a trouble light over a straight-six miraculously fed by a single-barrel carburetor while his father cursed the Blue Oval, all its products and everyone who ever worked there. This was his introduction to objective automotive criticism. He started writing for City News Service in Los Angeles, then moved to Europe and became editor of a car magazine called, creatively, Auto. He decided Auto should cover Formula 1, sports prototypes and touring cars—no one stopped him! From there he interviewed with Autoweek at the 1989 Frankfurt motor show and has been with us ever since.